In the divisions of England that took place between AD 613 and 1017, Buckinghamshire was divided into eight hundreds. The manor of Adstock originally formed part of the Votesdune Hundred, then merged into the Ashendon Hundred and was finally absorbed into the Buckingham Hundred. At that time it was surrounded by the Bernwood, one of the most important Royal Forests. At the end of the 10th century, Adstock formed a portion of the Lands of Godwine, Earl of Kent and his second wife Gytha Thorkelsdóttir.
In the mid to late 11th century the manor of Adstock was given by William the Conqueror to his illegitimate son William Peverel, who was listed as its owner in 1086. This suggests that the manor was of some value, or that its previous owner was of some prominence in Anglo Saxon society.
The village received a charter to establish itself as a town briefly in 1665 so that a market could be held there. This was due to the majority of the people from the two local towns of Winslow and Buckingham being infected with bubonic plague. The charter was removed, however, in 1685 and Adstock was reinstated as a village rather than a town.
The parish church, which dates from the 12th century, is dedicated to St Cecilia. The roof is dated 1597, and the church underwent further major restoration during the Victorian era. There are two bells (the lightest of which dates back from about 1440) in the church and one Sanctus
Adstock had an outstation from the Bletchley Park codebreaking establishment, where some of the Bombes used to decode German Enigma messages in World War Two were located.